Stomach woes

Project Details

Is it stomach flu or food poisoning?

You’re feeling nauseated and your stomach is cramping. You wonder, was it something you ate or a stomach virus?

The constellation of symptoms — nausea, abdominal pain, diarrhea and vomiting — are virtually the same whether the gastrointestinal distress is caused by a virus or a food-borne bacteria.

Doctors say it’s hard to pin down the cause by symptoms alone, and most people get better in a day or two without medical intervention.

When people do seek help, “it’s because they’re vomiting and haven’t been able to keep food down for a while or are dehydrated from severe diarrhea,” says UC Irvine Health emergency medicine specialist Dr. Shahram Lotfipour. “But it’s really hard to know if it’s food poisoning or not — unless they come in and say, ‘Hey, I just had some bad chicken or bad salad,’ or multiple people who ate it came down with the same symptoms.”

Food poisoning is caused by bacterial contamination and usually comes on within two to six hours of eating, whereas a viral infection can appear within a few hours or a few days after exposure, according to the National Institutes of Health.

Four viral groups cause most cases of gastroenteritis

Stomach flu is not a flu, which is a respiratory illness caused by influenza viruses. Rather it is a viral infection that attacks the gastrointestinal system. Viral gastroenteritis is usually caused by one of four types: rotavirus, adenovirus, astrovirus and the caliciviruses, the most common of which is the highly contagious norovirus.

Norovirus can be spread from person to person and by contact with surfaces touched days or weeks earlier by an infected person. It also can be transmitted by food handled by an infected person. In fact, norovirus causes 48 percent of food-borne illness outbreaks compared to 46 percent caused by the usual bacterial culprits — salmonella, E. coli, campylobacter, listeria and staphylococcus — put together, according to the Centers for Disease Control and Infection (CDC).

A norovirus outbreak was recently reported among students at Chapman University in Orange. It also has been implicated in recent restaurant outbreaks and is frequently found to be the cause of mass illness on cruise ships. Infants, small child and the elderly, especially those in long-term care homes, are particularly vulnerable to norovirus.

Tips to differentiate between food poisoning and a stomach virus

While it is hard to tell the difference between food poisoning and a stomach virus without a test, there are some tell-tale clues, says UC Irvine Health infectious disease expert Dr. Shruti Gohil.

Acute stomach virus infections generally start with:

Nausea and/or vomiting

Watery diarrhea

Abdominal pain or cramping

Low-grade fever

Sometimes people also experience head and muscle aches as the infection runs its course. Symptoms usually resolve in one to three days, although it may take up to 10 days to completely recover, Gohil says.

Food poisoning, on the other hand, is caused by bacteria and can come on within hours of eating contaminated food. Symptoms include:

Abdominal pain and cramping that can be severe

Nausea and vomiting

Diarrhea

Fever and chills

If you develop a fever above 101.5 F (38.6 C) and chills, “you should see your doctor immediately,” Gohil says. “Some bacteria can be serious and lead to dehydration, kidney failure and arthritis. Depending on the cause, you may need antibiotics.”

Most food poisoning bouts clear up with a few days, although some can linger up to 10 days.

Stay hydrated while the infection runs its course

Whether it is food poisoning or viral gastroenteritis, treatment is essentially the same: Ride it out and stay hydrated, says the CDC. Drinking fluids that contain added electrolytes can be beneficial. Untreated dehydration can lead to severe health problems.

Take precautions to avoid spreading the infection

Because viral gastroenteritis is contagious and can stay in the gut up to two weeks after recovery, it is important to avoid spreading the infection, according to the National institute of Diabetes and Digestive and Kidney Diseases, which recommends that patients and their caregivers take the following precautions:

Wash hands in warm, soapy water for at least 20 to 30 seconds after using the bathroom or changing diapers and before eating or handling food.

Clean contaminated countertops and other surfaces with a mix of one cup of household bleach to a half-gallon of water.